The mod_ssl package name could be overridden in apache:lookup:mod_ssl.
Due to the way lookup keys are merged into the main apache dictionary,
the package name clashed with the mod_ssl configuration defined under
apache:mod_ssl.

Fix that by renaming the mod_ssl package variable to mod_ssl_pkg.

Drive-By: Add mod_ssl_pkg to the pillar.example file.

```bash
apache-formula$ yamllint -s .
./pillar.example
  2:1       warning  missing document start "---"  (document-start)
  5:26      warning  truthy value should be one of [false, true]  (truthy)
  50:18     warning  too few spaces before comment  (comments)
  51:16     warning  truthy value should be one of [false, true]  (truthy)
  52:57     warning  too few spaces before comment  (comments)
  52:89     error    line too long (104 > 88 characters)  (line-length)
  67:33     warning  truthy value should be one of [false, true]  (truthy)
  67:38     warning  too few spaces before comment  (comments)
  69:31     warning  too few spaces before comment  (comments)
  70:8      warning  missing starting space in comment  (comments)
  75:53     warning  too few spaces before comment  (comments)
  75:89     error    line too long (98 > 88 characters)  (line-length)
  76:55     warning  too few spaces before comment  (comments)
  76:89     error    line too long (101 > 88 characters)  (line-length)
  78:50     warning  too few spaces before comment  (comments)
  79:89     error    line too long (95 > 88 characters)  (line-length)
  82:47     warning  too few spaces before comment  (comments)
  83:54     warning  too few spaces before comment  (comments)
  83:89     error    line too long (100 > 88 characters)  (line-length)
  84:58     warning  too few spaces before comment  (comments)
  84:89     error    line too long (109 > 88 characters)  (line-length)
  93:32     warning  too few spaces before comment  (comments)
  100:89    error    line too long (105 > 88 characters)  (line-length)
  101:33    error    trailing spaces  (trailing-spaces)
  102:16    warning  truthy value should be one of [false, true]  (truthy)
  231:20    warning  truthy value should be one of [false, true]  (truthy)
  242:32    warning  too few spaces before comment  (comments)
  249:20    warning  truthy value should be one of [false, true]  (truthy)
  254:20    warning  truthy value should be one of [false, true]  (truthy)
  260:21    warning  truthy value should be one of [false, true]  (truthy)
  283:8     warning  missing starting space in comment  (comments)
  284:8     warning  missing starting space in comment  (comments)
  297:15    warning  too few spaces before comment  (comments)
  328:18    warning  truthy value should be one of [false, true]  (truthy)
  330:20    warning  truthy value should be one of [false, true]  (truthy)
  342:15    error    empty value in block mapping  (empty-values)
  345:18    warning  truthy value should be one of [false, true]  (truthy)
  348:18    warning  truthy value should be one of [false, true]  (truthy)
  355:18    warning  truthy value should be one of [false, true]  (truthy)
  358:89    error    line too long (91 > 88 characters)  (line-length)
  359:26    warning  truthy value should be one of [false, true]  (truthy)
  362:89    error    line too long (99 > 88 characters)  (line-length)
  365:89    error    line too long (267 > 88 characters)  (line-length)
  367:21    warning  truthy value should be one of [false, true]  (truthy)
  369:26    warning  truthy value should be one of [false, true]  (truthy)
  371:1     error    too many blank lines (1 > 0)  (empty-lines)

./apache/osfingermap.yaml
  3:1       warning  missing document start "---"  (document-start)

./apache/modsecurity.yaml
  4:1       warning  missing document start "---"  (document-start)
  6:18      warning  truthy value should be one of [false, true]  (truthy)
  7:20      warning  truthy value should be one of [false, true]  (truthy)
  14:18     warning  truthy value should be one of [false, true]  (truthy)
  15:20     warning  truthy value should be one of [false, true]  (truthy)
  22:18     warning  truthy value should be one of [false, true]  (truthy)
  23:20     warning  truthy value should be one of [false, true]  (truthy)

./apache/defaults.yaml
  4:1       warning  missing document start "---"  (document-start)
  5:26      warning  truthy value should be one of [false, true]  (truthy)
  7:19      warning  truthy value should be one of [false, true]  (truthy)
  10:18     warning  truthy value should be one of [false, true]  (truthy)
  11:20     warning  truthy value should be one of [false, true]  (truthy)

./apache/oscodenamemap.yaml
  4:1       warning  missing document start "---"  (document-start)
  4:8       error    trailing spaces  (trailing-spaces)
  9:8       error    trailing spaces  (trailing-spaces)
  14:7      error    trailing spaces  (trailing-spaces)
  19:6      error    trailing spaces  (trailing-spaces)
  24:8      error    trailing spaces  (trailing-spaces)
  29:9      error    trailing spaces  (trailing-spaces)
  34:7      error    trailing spaces  (trailing-spaces)
  39:8      error    trailing spaces  (trailing-spaces)
  44:8      error    trailing spaces  (trailing-spaces)
  50:9      error    trailing spaces  (trailing-spaces)
  61:1      error    too many blank lines (1 > 0)  (empty-lines)

./apache/osfamilymap.yaml
  4:1       warning  missing document start "---"  (document-start)
  16:89     error    line too long (104 > 88 characters)  (line-length)
  43:89     error    line too long (105 > 88 characters)  (line-length)
  56:16     warning  truthy value should be one of [false, true]  (truthy)
  114:11    error    empty value in block mapping  (empty-values)
  114:11    error    trailing spaces  (trailing-spaces)

./test/salt/pillar/default.sls
  5:26      warning  truthy value should be one of [false, true]  (truthy)
  7:18      warning  truthy value should be one of [false, true]  (truthy)
  8:20      warning  truthy value should be one of [false, true]  (truthy)
```